Biomedical subjects

Hideaki Tanaka

Publications and source records attributed to Hideaki Tanaka.

57 records · Page 4Linked to original sources

PubMedDate not supplied

Differences in attitude toward living and postmortal liver donation in the United States, Germany, and Japan.

Living liver donation is a possible immediate option for decreasing the shortage of liver allografts worldwide. Risks related to the donation make this procedure ethically controversial. Study groups of medical students (N= 330) from three different nations were analyzed with a complex questionnaire, and data were subjected to multiparameter analysis. The readiness for living liver donation was dependent upon the cultural background of the study groups. It was higher in the U.S. than in Germany and Japan, with a higher donation readiness for children as recipients than adults. Major differences among distinct sociodemographic groups need to be carefully addressed when setting up consensus guidelines for the clinical practice of living donation.

Adult↗

PubMedDate not supplied

Changes in translucency and color of particulate filler composite resins.

PURPOSE: The purpose of this study was to examine changes in translucency and color of particulate filler composite resins that can be fabricated into metal-free crowns. MATERIALS AND METHODS: Eight types of materials were used in this study. The particulate filler composite resins were represented by Artglass, BelleGlass, Estenia, Gradia, and Targis. Herculite XRV and Solidex were the conventional composite resins for crowns and fixed partial denture facings, and Empress was the ceramic material. Disks with a thickness of 1.0 mm were fabricated from each material and subjected to an accelerated test by immersion in 60 degrees C distilled water for up to 8 weeks. Color measurements were made before and after water immersion. Changes in translucency were evaluated by determining the contrast ratio, and changes in color were evaluated by determining color difference. RESULTS: After water immersion, Targis and Solidex demonstrated a significant increase in contrast ratio (6% to 7%) and a decrease in translucency. A color difference of more than 2.0, a visually perceptible value, was found for Targis, Gradia, and Solidex. However, the maximum color difference for these was 3.0, a value that would be considered clinically acceptable. CONCLUSION: Within the limitations of this study, the particulate filler composite resins were stable in both translucency and color.

Aluminum Silicates↗

PubMedDate not supplied

Strength and elastic modulus of fiber-reinforced composites used for fabricating FPDs.

PURPOSE: The purpose of this study was to examine the flexural strength and elastic modulus of a new fiber-reinforced composite used for the fabrication of inlay-retained fixed partial dentures (FPD). MATERIALS AND METHODS: A total of six materials were used: Vectris, FibreKor, and an experimental material, BR-100, were the types of glass fiber preimpregnated with resin used for making the frameworks; Targis, Sculpture, and Estenia were used as the veneering composites. Five specimens of each material were prepared. Flexural strength and elastic modulus were determined using the three-point bending test. In addition, laminate specimens were fabricated by combination of the veneering composite and framework materials (Targis/Vectris, Sculpture/FibreKor, and Estenia/BR-100), and fracture loads of these specimens were determined. Laminate specimens were fabricated with three different framework thicknesses for Estenia/BR-100. RESULTS: Estenia had the greatest strength and highest modulus of elasticity of the veneering composites. All three framework materials had flexural strength values (567 to 686 MPa) more than three times as great as those of the veneering composites (132 to 193 MPa). Of the laminate specimens, the Estenia/BR-100 with a framework thickness of 1.0 mm had a fracture load more than 50% greater than Targis/Vectris and Sculpture/FibreKor. CONCLUSION: The combination of the experimental framework material BR-100 and the composite Estenia showed higher fracture loads than the other combinations tested.

Composite Resins↗